Clicking on “Download new version” in the window below should open Unity Hub and install the new version. It opens a browser window instead.
@LeonhardP Not sure where to post this request since it’s related to both the editor and the hub, so I posted it here. 
Thanks @ , I’ll talk with the team.
I second this - especially newer users often wonder that they have to redownload unity - redirecting them to the hub for downloading the new version should make it clear for them, that there is a manager that supports multiple installs/versions.